As its name implies , this form of heating is used to balance or compensate for heat losses from a pipeline to the surrounding atmosphere. The following formulae may be used to calculate the amount of heat required:
Heat loss balance for pipelines
W = 2.75k (T-t) W/m
E .log 10 (D/d)
Raising Temperature of pipelines
In the majority of cases, it’s more economical to maintain the heating over short shutdown periods, e.g. weekends than to make provision for heating up from cold. Where its essentials to provide sufficient heat for warming up in addition to heat loss compensation, the time allowed for warming up should be 12-24 hours, as shorter periods normally involve inconveniently high loadings.